Internal combustion engine



June 22, 1943. H .-O. HEDGES 2,322,293

INTERNAL COMBUSTION ENGINE Filed Jan. 24, 1942 a INVENTOR Patented June 22, 1943 UNITED STATES PATENT OFFICE 2,322,293 7 g INTERNAL COMBUSTION ENGINE Harry 0. Hedges, Seattle, Wash.

Application January 24, 1942, Serial No. 428,070

1 Claim. (01. 123-63) This invention relates to improvements in internal combustion engines, and it has reference more particularly to the cooling of engines of the double acting type, wherein the engine's pistons are reciprocally driven by the synchronized admittance and exploding of fuel charges within both ends of the cylinders.

In my copending application, filed on October 4, 1940, under Serial No. 359,713 now Patent No. 2,295,037, Sept. 8, 1942, I have illustrated an engine, designed to operate on the two-stroke cycle principle, Whereas this application discloses the invention as it concerns the cooling of the pistons, as applied to an engine of the double acting type and operating on the four-stroke cycle principle. The present application is a continuation in part of the pending application.

It is the principal object of this invention to provide an engine of the double acting type, operatin on the four-stroke cycle principle and including the air cooling facilities of the above mentioned application for the effective and practical cooling of the engines piston.

More specifically stated, the objects of the present invention reside in the provision of an internal combustion engine of the double acting type, operating on the four-stroke cycle principle, and having its power piston equipped with a passage transversely therethrough for passage of coolin air. Also, having the cylinder in which the piston is contained, equipped with oppositely disposed side wall ports, one of which is connected with a source of supply of cooling air under pressure, and across which ports the ends of the passage in the piston are caused to pass in registration, thus to allow a blast of cooling air to be delivered therethrough with each reciprocal action of the piston.

Still further objects of the invention are to be found in the details of construction and combination of parts, as will hereinafter be fully described.

In accomplishing these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawing, wherein-.-

Fig. 1 is a longitudinal section of an engine embodying the improved features of the present invention.

Fig. 2 is a cross section on the line 22 in Fig. 1.

Fig. 3 is an end View of the engine.

Fig. 4 is a section on line 4-4 in Fi 1.

Referring more in detail to the drawingends of the power cylinder 4 are closed, respec- I designates the crank case housing of the engine, and 2 the engine crank shaft revolubly supported in bearings 3 and 3' mounted in the housing. Mounted on the crankcase housing, at one side thereof, is a power cylinder 4, made in accordance with details of this invention. This cylinder is mounted by a hollow base section 5 which, in turn, has its inner end portion fitted in a side Wall openingof the crank case housing and fixed rigidl to the wall. The inner and outer tively, by the cylinder'heads Sand 1, and a piston Ellis reciprocally contained in the cylinder.

The piston it is fixed to the outer end of, a piston rod H that is slidable through a packing 'sleeve. l2 fitted in the opening in the cylinder head wall 6, and this rod extends into the cylinder mounting section 5. At its inner'end, this rod has fixed-connection with a cross head I4, and at its opposite ends, the cross head mounts roller bearings l5l5' thereon. The roller bearings I5 and I5 are each contained, in rolling contact between parallel guide rails 16 and I6, integral with the section 5 and extending lengthwise of the direction of travel of the piston rod. A connecting rod l8 has pivotal connection at one end with the cross head [4 and at its other end is operatively connected with a throw 2a of the crank shaft 2. Thus, through this connection, which is more completely described in the above mentioned copending application, reciprocal action of the piston in its cylinder will impart rotary motion to the crank shaft.

Mounted at one end of the crank case housing and axially alined with the crank shaft, is an air fan housing 20, and from this housing, an air delivery manifold 2| extends to the cylinder 4. This manifold opens directly into the cylinder at a point medial of its ends through a side Wall port 22. In the opposite side of the cylinder diametrically opposite the wall port 22, is a similar port 23 for outflow of the cooling air, as later will be explained.

Contained in housing 20 is an air blower fan 24 mounted on a fan shaft 2'4 that is rotatably supported in the housing in suitable bearings designated at 25. The shaft 24' is driven by reason of a driving connection made at its inner end with the crank shaft 2 through a gear train designated at 26 in Fig. 1. The gear ratio of this train is such as to increase the speed of the fan substantially above that of the shaft, thus to cause it to furnish an adequate supply of cooling air, under pressure, to the cylinder through manifold 2|.

The length of the piston 10 is somewhat greater than its extent of reciprocal travel in opposite directions, and it is so disposed in the cylinder that it will not uncover the ports 22 and 23 as it reciprocates.

It will be observed, by reference to the drawing, that the piston I is substantially hollow and is closed at both ends, respectively, by walls Illa and lb. Also, it will be observed that the piston is provided at opposite sides with relatively large openings 35 and 36 which provide a passage directly through the hollow body. These openings or ports 35 and 36 are adapted to simultaneously move across the openings 22 and 23, as the piston reciprocates. Thus, with each reciprocal movement of the piston in either direction across port 22, a cooling blast of air will be delivered therethrough.

It is desirable that the piston body be formed internally with longitudinal cooling fins 38 as will be understood by reference to Fig. 4.

The inner end wall [0b of the piston ID has a central opening 39 in Which the reduced end portion ll of the piston rod II is contained and secured by a nut 40 that is threaded onto this end of the rod to seat against the inner face of the wall.

In this engine, the cylinder heads 6 and 'l are equipped for mounting spark plugs 50 for the ignition of the fuel charges. Also, provision is made for the admission of fuel charges at both ends of the cylinder from fuel supply manifolds 52 under control of poppet valves I, and burned charges are exhausted from the cylinder under control of valves 53, into a manifold 54. These valves 5| and 53 may be yieldingly held closed by springs, as shown at 55 and may be opened in proper timing within the piston travel by any of the conventional means used in engines of this kind, not herein shown in detail, but usually operated by cams on a shaft driven from and and in synchronism with the rotations of the crank shaft.

With the cylinder and piston so constructed, it is readily apparent that effective cooling of the piston will be attained by reason of the fact that each time it moves from one end of the cylinder to the other, it causes its transverse channel to pass in registration with the supply of cooling air, and a blast of cooling air will be delivered directly therethrough. The particular internal structure of the piston facilitates the cooling operation.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent is:

In a double acting internal combustion engine of the character described, a cylinder, closed at its opposite ends and equipped with means at both ends for the admittance and ignition of fuel charges thereinto and for the exhaustion of burned charges therefrom, and having air inlet and outlet ports in its side walls intermediate its ends, and a piston reciprocally contained in the cylinder, and having a cooling passage therethrough adapted, with movement of the piston from one extreme to the other, to pass in registration with said air inlet and outlet ports for the delivery of cooling air through the piston and cylinder; said piston at all times overlapping said ports at the end of each stroke to prevent entry into the combustion chamber.

HARRY O. HEDGES. 

